package com.maltys.dp.sequence;

/**
 * @author malty
 * @link <a href="https://leetcode.cn/problems/delete-operation-for-two-strings/">两个字符串的删除操作</a>
 */
public class DeleteTwoStrings {
    public static void main(String[] args) {
        DeleteTwoStrings deleteTwoStrings = new DeleteTwoStrings();
        int distance = deleteTwoStrings.minDistance("seat", "feaq");
        System.out.println(distance);
    }

    /**
     * case: "sea", "eat"
     * 相等的时候
     * dp[i][j] = dp[i - 1][j - 1]
     * 不相等的时候
     * dp[i][j] = min(dp[i - 1][j]+1, dp[i][j - 1]+1, dp[i - 1][j - 1])
     *
     * @param word1
     * @param word2
     * @return
     */
    public int minDistance(String word1, String word2) {

        int[][] dp = new int[word1.length() + 1][word2.length() + 1];
        for (int i = 0; i < word2.length(); i++) {
            dp[0][i] = i;
        }
        for (int i = 1; i < word1.length(); i++) {
            dp[i][0] = i;
        }
        for (int i = 1; i <= word1.length(); i++) {
            for (int j = 1; j <= word2.length(); j++) {
                if (word1.charAt(i - 1) == word2.charAt(j - 1)) {
                    dp[i][j] = dp[i - 1][j - 1];
                } else {
                    dp[i][j] = min(dp[i - 1][j] + 1, dp[i][j - 1] + 1, dp[i - 1][j - 1] + 2);
                }
            }
        }
        return dp[word1.length()][word2.length()];
    }

    private int min(int i, int i1, int i2) {
        return Math.min(i, Math.min(i1, i2));
    }
}
